Normal air diffusion reduces tire pressure over time so that the natural state of tires is underinflated. Accordingly, drivers should constantly check tire pressure to avoid increased fuel consumption or wear and to avoid impeded braking and/or handling performance. Even more, a substantially underinflated tire may constitute a severe safety risk. Tire pressure monitoring systems have been proposed to warn drivers when tire pressure is significantly low. Such systems, however, remain dependent upon the driver taking remedial action when warned to reinflate a tire to a recommended pressure.
It is desirable, therefore, to provide components which allow or help to provide an automatic inflation of a tire without requiring any action of the driver. Of course, these components should be easily and cost-effectively mountable to the tire.
Document US 2013/0048178 A1 discloses a self-inflating tire assembly including an air tube connected to a tire and defining an air passageway. The air tube is sequentially flattened by the tire footprint in a direction opposite to a tire direction of rotation to pump air along the passageway into the tire cavity. An inlet device is positioned within the annular passageway 180 degrees opposite to an outlet device such that the sequential flattening of the air tube by the tire footprint effects pumping of air along the air passageway with the tire rotating in either a forward or reverse direction of rotation. The assembly includes also an inlet device for regulating the inlet flow of the air tube pump, wherein the inlet device is fixedly mounted within the tire's sidewall.